// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_HOST_H_
#define CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_HOST_H_

#include "base/environment.h"
#include "base/memory/shared_memory.h"
#include "base/process/kill.h"
#include "base/process/process_handle.h"
#include "base/strings/string16.h"
#include "build/build_config.h"
#include "content/common/content_export.h"
#include "content/public/common/process_type.h"
#include "ipc/ipc_sender.h"

#if defined(OS_MACOSX)
#include "base/process/port_provider_mac.h"
#endif

namespace base {
class CommandLine;
class SharedPersistentMemoryAllocator;
}

namespace content {

class BrowserChildProcessHostDelegate;
class ChildProcessHost;
class SandboxedProcessLauncherDelegate;
struct ChildProcessData;

// This represents child processes of the browser process, i.e. plugins. They
// will get terminated at browser shutdown.
class CONTENT_EXPORT BrowserChildProcessHost : public IPC::Sender {
public:
    // Used to create a child process host. The delegate must outlive this object.
    // |process_type| needs to be either an enum value from ProcessType or an
    // embedder-defined value.
    static BrowserChildProcessHost* Create(
        content::ProcessType process_type,
        BrowserChildProcessHostDelegate* delegate);

    // Used to create a child process host, connecting the process to the
    // Service Manager as a new service instance identified by |service_name| and
    // (optional) |instance_id|.
    static BrowserChildProcessHost* Create(
        content::ProcessType process_type,
        BrowserChildProcessHostDelegate* delegate,
        const std::string& service_name);

    // Returns the child process host with unique id |child_process_id|, or
    // nullptr if it doesn't exist. |child_process_id| is NOT the process ID, but
    // is the same unique ID as |ChildProcessData::id|.
    static BrowserChildProcessHost* FromID(int child_process_id);

    ~BrowserChildProcessHost() override { }

    // Derived classes call this to launch the child process asynchronously.
    virtual void Launch(
        std::unique_ptr<SandboxedProcessLauncherDelegate> delegate,
        std::unique_ptr<base::CommandLine> cmd_line,
        bool terminate_on_shutdown)
        = 0;

    virtual const ChildProcessData& GetData() const = 0;

    // Returns the ChildProcessHost object used by this object.
    virtual ChildProcessHost* GetHost() const = 0;

    // Returns the termination status of a child.  |exit_code| is the
    // status returned when the process exited (for posix, as returned
    // from waitpid(), for Windows, as returned from
    // GetExitCodeProcess()).  |exit_code| may be nullptr.
    // |known_dead| indicates that the child is already dead. On Linux, this
    // information is necessary to retrieve accurate information. See
    // ChildProcessLauncher::GetChildTerminationStatus() for more details.
    virtual base::TerminationStatus GetTerminationStatus(
        bool known_dead, int* exit_code)
        = 0;

    // Take ownership of a "shared" metrics allocator (if one exists).
    virtual std::unique_ptr<base::SharedPersistentMemoryAllocator>
    TakeMetricsAllocator() = 0;

    // Sets the user-visible name of the process.
    virtual void SetName(const base::string16& name) = 0;

    // Set the handle of the process. BrowserChildProcessHost will do this when
    // the Launch method is used to start the process. However if the owner
    // of this object doesn't call Launch and starts the process in another way,
    // they need to call this method so that the process handle is associated with
    // this object.
    virtual void SetHandle(base::ProcessHandle handle) = 0;

    // Returns the child message pipe token for the service request.
    virtual std::string GetServiceRequestChannelToken() = 0;

#if defined(OS_MACOSX)
    // Returns a PortProvider used to get the task port for child processes.
    static base::PortProvider* GetPortProvider();
#endif
};

}; // namespace content

#endif // CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_HOST_H_
